Whether you have a preferred font type or a compulsion to customise every single item you possibly can, Mail offers a comprehensive set of options to add a personal touch to its interface. Maybe you want to use a smaller font size in order to see more items or, conversely, you have an aversion to a cramped-looking application interface and prefer to give a lighter feel to its various elements. The Fonts & Colors preference pane is the place to go. The options presented there also give you the opportunity to alter the colour scheme of quoted text in your replies to messages.
In some cases, the choice of a specific typeface can lead to confusion. Fixed- width or mono-spaced fonts, like Courier, or varying width fonts, like Helvetica, can lead to uncertainty with characters like upper-case ‘i’, ‘1’ or lower-case ‘L’. This tutorial guides you through the font settings for the Mail viewer window.